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Wednesday, July 19, 2017

If, like me, you are a Blackberry 10.x user, you have probably been using FastTube for years not... not not and gave up like me... and then a couple of nights ago, was forced to stop using Whatsapp.
That annoying "switch to a supported device please" message that makes you furious to the core.

I've always been an android user... I have 3 android phones, 4 android tablets... and I must say I can live with android (normally after removing the operator and manufacturer bloat-ware)... but my side kick? my pocket secretary? that's the blackberry. It's always been, and I really hate that the community "try and force me out of something without first building something better for me to move to".

It's an easy (economics like) step to say "whatsapp is free, you need to use the devices we tell you to use"... but there is a reason why brilliant people are taught engineering at college instead of economics.

I hate those "non engineering, all economics, brainless decisions" and I also love a good challenge. So I took 5 minutes to digg deeper into this.

So sure the BB whatsapp is no longer supported... uninstall that crap, it will never work again.
However, the brilliance of BB system 10.x is that is has embedded android libraries as standard. That is why you can download .apk files and run it.
The problem is that most of those libraries are accessed by the GUI and the GUI from BB was built to use it's own functions.

Solution? Well why not installing a GUI manager for Android. Grab the "Nova launcher" APK and install it. All you need is to have BB OS 10.2 up... I'm using 10.3. The other APK you really need is the Playstore apk. Even if it does not run, some APK's check for it at launch so "being there" is important.

One of the apks that you can install is the Watsapp apk... and believe-me... it runs perfectly.

No need to buy a new phone... just to digg into the BB OS10 project and be amazed with the similarities between the 2 xNIX platforms and their respective support framework.

Friday, August 26, 2016

This article is pretty useless without first reading the Part1, so if you haven't read that you will not understand the whys in this one.

Ok so I dealt with the first part of the problem with Part1... but that still leaves me with the even bigger, even more asymmetrical, prone to echoes and natural amplification of sound Cinema and Games Room.
There is another catch: the living room was supposed to have good sound, but this has to have good and powerful sound! If I'm having a party, this will be the disco.

The geometry, already discusses in Part 1 is...

...challenging.

So, again, after several tests and trials, and the obvious usage of my Galaxy Alpha phone as a sound analyser, I managed to sort things out this way: (for the geeks sake, I'm starting will the schematics and all the goodies, and I'll explain as I go.

OK so this is far more complex (starting with the inputs... being a cinema and game room and all)!

The inputs start with the so full of glamour and on of the best CDPlayers EVER made the Nakamichi CD2P-E. This thing has been recapped and ouptup XOver trimmed so that all the possible musical details are pickup. This is an example of why a good old 16Bit DAC CDPlayer can eclipse an modern 24bit DAC cd player... I could talk for a year on this, but in very simple terms, think that the analog sound wave that you hear, once digitized is converted to a sort of bar chart of what the music would look like. Obviously, this loses resolution and that is why a true audiophile prefers vinils to CD's.
However, there are some excellent designs out there that can "imagine" the gap between the bars and recover the lost sound-wave. Some are good.. some are great and some are gods.
So in this sense, more bits = more resolution = better sound...no! CD's where recorded with a specific bit-stream in mind... having more bits does not mean that you have more resolution out of the CD, but rather you can decode more at once, and that allows you to have a bit-stream comparison on the recreation of the sound wave that could reduce conversion error.... so a 8 parallel chip 16bit circuit will easily eclipse a state of the art 24bit DAC (if the 16bit chips are really good).

Back then, while Philips created the TDA1541A 16bit DAC chip (and they did a VERY good job at that), they also created what is called a reference diagram, so that integrators could follow and create their own design. These diagrams normally are a schematic build to make the chip work and they are build long before the chip is made... so, by other words, no one ever tested the diagram.
Pioneer, sony, and all the other except Nakamichi and Arcam, decided to copy-paste the schematic and sell cd players.
Did it work? yes! Where they any good?.. no! they where all mostly dull and flat. Nakamichi and Arcam, however, waited for the chip, built their board based on the reference but not blindly, and then tweaked the output and voila! They unlocked the secrets of the brilliance of Philips TDA1541a chip design.
It is one of the best DAC out there!

The CD2P is rare for being very pure and precise in sound image, and shows you the best details in sound. It's that sort of player that makes you re-listen to all your collection because there was just too much you where missing.

As usual, loving he best ever build and being a child from the 70's-80's, I have my Amiga 1200 Tower connected to my media sytem.
You can see it here:

The rest is the typical Nintendo Wii, a Sony PS3 and a Roku3.

The AVR:

The AVR is a Denon4306... a true beast

This, is directly driving the Front L+R, the Midle L+R and the Rear L+R... and then it pre-outs the subwoofer and the Rear and Center channel to a set of slave amplifiers. The direct drive from the Denon outputs 8Ohm at 130RMS watts, and given the generous size of the capacitors, it's no wonder it can drive the speakers without getting tired when a lot of bass kicks in. The Denon has a capacity to resist starvation that is not all that common.

The central front slave to the Denon is no less than a Marantz PM55SE... yes it is a Ken Ishiwata tuned PM55... special edition.
A beauty...with a total harmonic distortion of 0.02%

This then drives directly a pair of B&W DM305. The 305 was an interesting project.
B&W where on the quest for a deep bass speaker made form light materials, that could reproduce across the range and not suffer form brittleness form the light materials resonance, and still provide some bass.
They created a Prism design backplane for the speaker that mimics the attenuator foam form the walls of any sound proof room.

Did they succeed? NO! the bass is to soft (probably attenuated by the prism), however, they are EXCELLENT to reproduce voice channels... like the typical "dialogue" assignment that a THX system enrols the central channel into. So an initial deception as main speakers, transformed into a solution for the central channel. Driven by a powerlfull bu low distortion amp.

Back to the Amps... so I talked about the front, so how about the reinforced back?
The room architecture meant that rear needed power, so instead of buying
extra big speakers and loose HIFI, I chose to spread the frequencies
across multiple speakers and make a "sound wall".

Welcome to my faithful Marantz PRO PM4400

Once again, I turn to Marantz this time seeking power and precision.
This beast is directly driving:

The Mission 773 pair and the Celestion Impact s1 10"sub

The Missions will be talked about soon enought, so let's look at the celestion! This 10" driver with it's own poweramp and XOver, is able of going below 30Hz (normally you would go for a 12" and more to run below 30hz). we can;t however forget that celestion is the brand behing most rock concerts speakers, the bass stations on most dance clubs and, last but not least, a major builder and suplier of drivers for other speaker manufacturers.
Yes, their driver can go bellow 30Hz and still be able to go up to 150Hz because of the stiff and light construction.

But we are not done with the Marantz PM4400 yet.... out of the back of the Celestion, Xover to 150Hz and up, there are a couple of Mission 772 on a pair of ATACAMA stands.

Now lets look at the speakers that the Denon drives directly:
Starting with the back (since we where already there), a pair of Mission 774

On the Middle we have a pair of very powerfull and robust Wharfedale XARUS 4000:

The finally, the best sounding speakers for the money ever built, driven direclty by the Denon on the front R+L channels, a pair of Mission 782.
These are very peculiar speakers that have a very interesting history, please read all about it here.

We can't forget that the mid-to low bass is output by a KEF 1000.2

The result? please have some pictures:

This is a Video of the Sound quality and image, with "The Verve's - Happy Man" brutal guitar:

Here, it is clear that the camera mic is on the limit with just a simple guitar playing as -20db, and when I up to -10db is just distorts the pickup sound. But believe-me... the listening experience is flawless if you have ears instead of a cheap MIC.

And this is a video demonstrating how easy this handles pure bass, at volume, without distortion or brittleness:

Without surprise, the Mic is not able to perform at -20db with a bass full music, the 10db is just pure distortion on the MIC.

However, looking at the graphs several conclusions can be taken on both videos:

The system is reproducing at 24hz frequency and performs all the way up to 20khz without gaps

When the volume is increased, the system increases db's without compromising the frequencies... they all grow proportionally.

The Bass (hard to equalize) is maintaining the volume without gaining HUMMMMsss or becoming excessive.

The volume at -20db is enough to overwhelm a Splash Action cam's mic...with rock!

The 772 and 773 speakers are operating near the limit on the -10db with bass sound, I'll try to attenuate this in the future, so i can go all the way up to 0db and eventually end up without windows in my place :)

Now about the Missions... all the 772, 773, 774, 782... together with my M73i, V62 and the Mission built Denon SCM51.

Some would ask, do you have a mission fetish?
No! I have an engineering over economics fetish... that's why.
It's easy to grab the best materials out there and, not minding cost, build a decent speaker that the client would buy for gazillion euro and perform nicely!

Mission is that brand that (in the old days) invested a lot of engineering time trying to create a speaker design that performed the best, and then try to replicate that design with materials that would cost less, so the client would not need to overpay (sometimes this came back to bite them, but some years in and a small research can turn this around in your favour... see my Mission 782 article).
The result is that most OLD missions sound better than their price range. But every now and then they build a product that rockets out of their standard into stratospheric performance.
The 782 is an example of that! It sounds better than speakers costing 10 times as much. Much like the M73i and V62 (after properly sanded with a minimum 2kg of sand) can sound better than speakers that cost 4 to 5 times as much.
The 772, 773 and 774 are a family of speakers that are excellent performers for the price... but within this family, the 774 is the excel. It just sings through the entire frequency range without a fuss.... it's far better than the cost.

Why? Well, just like B&W has John Bowers, Marantz has Ken Ishiwata, Mission had Peter Comeau.
Most speaker I buy are designs produced by or supervised by Peter Comeau. We seem to like the same things and that is very good... plus I love the idea of not paying for others laziness (nor marketing... hence not owning a single Bang&Olufsen).

Hope you like this article... more will follow are there are 5 other audio systems that make me very happy and proud... and will make their way into the next 5 articles, so stay tuned.

Thursday, August 25, 2016

I'm very happy with my new house and the so very cool 2 living-rooms divided by a mezzanine thing.
So I decided to transform the top living room into a "cinema and game room"... while the downstairs living room stays as such.

Problem? Well there is a point in which I'll have to equip with some decent audio, and taking into consideration the size and geometry of the 2 rooms I was in for a challenge.
Why? well I love hi-fi, so big speakers and loads of volume would solve the room size problem... and kill quality and sound image while creating weird re-verbs and echoes.
So I started a project of trial and error till I had everything I wanted.

Lets start with the problem:

OK, so I have a Big room sized as an amplifier cone, all with hard surfaces, but then with a bottom cut on the back that leads to another big room.

Then on the bottom room, I have a change form 3 to 6 meters in hight, asymetric and in the middle of the room, right where the big and bass eating sofa will be placed.

Things do not seem easy.

So lets start by the Bottom Room, the living room with a bass propagation problem and a excessive treble at the rear issue:

I love movies, so my buy was an LG 65" LCD 3D TV.... that consumes almost all available space between the entry door and the fireplace... right in front of the extendible sofa with chaise-long...perfect.

Managing the AV system is an HarmanKardon AVR355 7.1 system. Very involving and warmed sound amp.
The HK355 then feeds the central, front and rear channels to a Bose Acoustimass system. I know there are a lot of haters for the BOSE acoustimass system out there, but bare in mind this was chosen after several tests for an even distribution of sound...hence the usage of the JEWEL dual Cubes instead of the single cubes.
This then leaves the middle channel to a pair of brilliant B&W RockSolid speakers.

This builds a basic and respectable 7.1 system capable of handling most frequencies... but no earthquake bass.
So another Subwoofer was added. After several tries ranging from a kef 1000.2 to a custom made 10", and locating every possible place on the room, I decided to reinforce the pure bass with a B&W ASW500, and place it pointing the sofa and in the middle of the room, right under the 3mts to 6mts ceiling high transition.

Everything seemed perfect, however, listening to music at the dining table at the back of the room (on the 6mts high ceiling section), sound seemed brittle and unbalanced... I tamed it down a bit by removing volume on the rear channel, but then that lost the detail on 7.1 movies every time something was coming in from behind!
It was clear that High-Low bass from the Bose acoustimass sub was not passing the sofa and having pointed the B&W rock solids to the middle of the sofa, the mid's where not propagating outside that area.
SO, I grabbed an excellent NAD302, fed it to the pre-out output on the HK355 for the middle channel and then managed a prodigious pair of Castle Acoustics Knight5 for it to drive.

Placing the Knights was easy too... right where the room grows from 3mts to 6mts, slightly towards the 6mts area.

Conclusion? a clean, perfect sound that, after some tweaking got balanced across the full range from the low 32hz to the higher frequencies.
The listening experience is prime in the sofa, but very good everywhere in the room, the sound image and detail is amazing, and it's clear that the BOSE system can handle voice channels very well, but they are eclipsed with easy by the B&W RockSolid and the amazing Castle Acoustics.

So schematics for the geeks:

So the trick to make the BOSE system bearable (yes I know they are expensive and not brilliant, but they are very powerfull for the size and allow me to distribute sound better than a single Kef EGG and less open than a bipolar setup... believe-me I' have them all and tried them all)...so the trick... do not allow them ever to go under 200Hz... on only they sound fuzzy, you can also burn them up.

Again, the trick to make the acoustimass fake Subwoofer (it is actually a resonance box with 2 internal, very stiff, 6" woofers that either blow at the same time for a lower frequency response, of individually for a mid-bass range)... is not to drive it below 80Hz... yes it can do that, but it is not the comfort zone and it is also pointless if you have a big room with a bigger sofa in front of it... so just allow it to work the 80hz to the 160hz zone and he will be happy as a kid in xmas.

So pure bass that makes the earthquake in the movie a thing of reality in your room: Welcome to B&W ASW500. I chose this because with a 10" long-throw front faced driver, fed by a internal 70W amp. Unlike most designs I tested (down firing designs), this front firing model with a down firing resonance amplifier is the best choice for the current furniture setup.
This sends most of the powerfull soundwave directly into the sofa, and the eco on the living room is the resonance output effect, minimizing the HUMMM effect that was so obvious with the down-firing designs. This beast is XOvered to work the 30 to 80Hz range.

So we have covered 30 to 80Hz, then 80 to 160Hz and then 200Hz to 20KHz. The Jewels Dual Cube allow for distribution, making the sound fill the room without the need to pump the volume up, avoiding high pitch echoes and uncomfortable listening spots.

Yes.... that leaves a gap on the 160hz to 200hz range... but fear no more... B&W is here. The RockSolids are a thing of wonder.... product of a disagreement between the 2 major partners at B&W - back then, the engineer was trying to experiment new materials with the standard designs while the artist was not happy with that and was pointing investment towards new case designs more on the "sound furniture style".... they split and the engineer decided to create RockSolid Sounds, and eager to try new materials, experimented on this model creating a 150W capable wonder. They then buried their "tomahawks" and fused the 2 companies together. This design fathered today's DM1 series... however it is far more ugly and that is why I like it... the ugly part is the result of an old design sound box that server the engineering purpose. Consequence? The Rock Solids sound better than the beautiful DM1 they fathered.
These things can work form 75hz to 20kHz! however, the physical limitation of a small driver putting out big quantities of air is clear and that is why a good Sub is over 8" big. So they are XOver at 120Hz to the 20Khz limit.

We are then left with the room side and weird geometry solution. While B&W where fighting over the external design of their speakers, trying to build "sound furniture", at Castle, they've always bee there. Every speaker is made from natural wood, carved by artisans. They also have a Dual Pipe technology, that channels air through several wooden compartments on the speakers body (much like a exhaust muffler, only sophisticated and matured to perfection... they don't sound good... they sound really really good! In practice, the speaker is a true 3 way design, but each mid and mid-low driver has it's own compartment and sound pipe to work the resonance down and up the speaker body...it doesn’t sound... it's like it sings instead.
They are connected to the award winning NAD 302 and the result is a very composed and warm sound.
These are not crossed over... the NAD receives a pre-amp bypass from the AVR and amplifies it, then the internal XOvers on the speaker will split the high, mid and mid-low and allow the resonance pipes to work their magic.

The result is a very balanced output, across all the frequency range.. and qith the NAD running tone-defeat and the Harman-Kardon too, I have literally no distortion up to the 0DB resistance limit on the HK... sure that by then the B&W rock solids cones are almost jumping out of their structure, but the castles compensate whatever they lose to low frequencies and it is almost imperceptible.

Some pictures of the living room:

Here you can see the LG Tv, under it, you can see the custom made cabinet for the amps and the acoustimass bass module. On both corners an center on the ceiling line you can see the Jewel Dual Cubes placed to distribute sound as even as possible.

Here in detail, the Jewel Dual Cube angles

Here are details on the HK AVR355 and the NAD, together with the Bose Acoustimass bass module

The brilliant B&W RockSolids can be seen here in detail, and the 2 pictures bellow show them on the corners of the image, pointing to the sofa.

At the rear of the room, you can see the other jewel cubes in an elevated, pointing angled down position... and also the difference in hight that that part of the room has.

Now exactly where the room changes to a higher ceiling, I've placed the castles and the ASW500, see?

... and again here...

And to finish, the 2 beauties:

And that's it... the Living room is done and it is perfect. There where a lot of spares form the tests but I have other rooms I can use them in :) .

So Part 1 is done... next, Part 2 - The Cinema and Game Room... where I will have to deal with disco style amplification and the so needed NO distortions and excellent sound image, personal demand.